The present invention relates to coverings of the floor-covering type, for domestic, commercial or industrial use, especially indoors, which are applied to various surfaces, chiefly floors. These coverings are intended to wear on their outer surface under the action of various agents including treading by people. These coverings, flat and relatively flexible, can in practice take a continuous form, as a strip, sheet, roll and the like, or a non-continuous form, as separate components, for example slabs. These coverings are generally adhesively bonded no the surface which they are intended to protect.